This invention relates to sheet feeding apparatus, and more particularly relates to means for preventing feeding of doubled or overlapping sheets.
In feeding sheets, including currency and documents of various types such as checks, it is usually important that only one document at a time is fed. Various types of detectors for detecting the simultaneous feeding of multiple documents have been developed, as have various devices for preventing the feeding of more than one document at a time.
One such sheet separating device is disclosed in U.S. Pat. No. 3,052,465, in which a restraint belt cooperates with a sheet driving wheel to provide a sheet-driving throat therebetween. The sheet driving wheel drives sheets to be fed in a sheet advancing direction, while the restraint belt exerts a lesser force acting on the sheet surface adjacent to it to restrain movement of the sheet in the advance direction and thus separate any sheets which may be clinging together and which would otherwise be fed as a "double" in an improper feeding operation. A gravity operated arrangement maintains tension in the restraint belt and compensates for wear in the driving wheel and the restraining belt. A manually operated mechanism is provided to permit releasing of tension in the restraint belt and replacement of the belt and wheel when worn.
The apparatus of U.S. Pat. No. 3,052,465, in the form in which it is shown, does not appear to be adapted for feeding of vertically oriented sheets, because of the gravity-operated mechanism employed. Also, an increase in the compactness of such devices is desirable.